Soft matter with soft particles
In this review we present a summary of recent progress achieved in examining the equilibrium and dynamical properties of concentrated solutions of two novel kinds of soft matter systems: star-shaped polymers and starburst molecules known as dendrimers. The two systems share a host of interesting properties. The both consist of highly branched polymers, they allow for tuning of their properties through modification of the macromolecular architecture and they are both representatives of a quite novel class of colloidal particles, termed ultrasoft colloids. On the other hand there are also important differences, reflecting the fundamental difference in their architecture. It will be shown that a combination of scattering techniques and rheology with computer simulations and analytical methods from the realm of theoretical physics can shed light on the unusual properties of such systems. In this fashion, new ways appear for the manipulation of soft matter systems under external influences and promising perspectives for the fabrication of new materials are opened up and the versatility in manipulating soft matter is underlined.